JP5750085B2 - refrigerator - Google Patents

Description

  The present invention relates to a refrigerator that stores food, drinking water, and the like, and particularly to a refrigerator in which a photocatalyst is installed in a storage room.

  In recent years, with the increase in capacity of refrigerators, various foods have been stored, and interest in hygiene, sterilization, and deodorization in refrigerators has increased. For example, as a configuration for sterilizing and deodorizing the inside of a refrigerator, a configuration is known in which a photocatalyst having a sterilizing and deodorizing function is arranged in a cold air passage to remove odors and bacteria in the circulating cold air.

  For example, Japanese Patent Application Laid-Open No. 2003-322460 (Patent Document 1) describes a configuration in which a light deodorizing catalyst such as an ultraviolet light emitting diode and titanium dioxide is arranged in a cold air passage. In this configuration, the odor component in the cold air is adsorbed to the photocatalyst, the photocatalyst is activated by the ultraviolet light irradiated from the ultraviolet light emitting diode, and the odor adsorbed on the catalyst surface is oxidized and decomposed to be deodorized.

  Further, incandescent bulbs and the like have been used for the lighting device of the refrigerator, but the incandescent bulb has a problem that the amount of heat at the time of light emission is large and cooling efficiency is deteriorated. Therefore, light emitting diodes have come to be used as interior lighting that replaces incandescent bulbs. Light emitting diodes generate little heat and have high energy savings.

  Japanese Patent Laid-Open No. 2008-75887 (Patent Document 2) describes a configuration in which a photocatalyst is applied to a lamp cover or the like in a refrigerator, and the antifouling property and antibacterial property in the cabinet are enhanced by light irradiation with a light emitting diode. ing.

  In addition, a configuration has also been proposed in which a photocatalyst and a light emitting diode are arranged in a sealed storage chamber, and the organic gas in the storage chamber and odor components therein are deodorized by the photocatalyst.

JP 2003-322460 A JP 2008-075887 A

  By the way, in order to activate the above-described photocatalyst, it is necessary to supply power to an illumination means for irradiating light, for example, a light emitting diode. From the viewpoint of energy saving, it is necessary to suppress the power consumption as much as possible. However, the light emission control of the light emitting diode, which is an illuminating means for activating the photocatalyst so far, is configured to continue to irradiate a certain amount of light regardless of the state of the organic gas in the warehouse and the odor component therein. It was.

  For this reason, for example, when there is no or little food that generates organic gas or odor components in the refrigerator, it is not necessary to activate the photocatalyst. Unnecessary power was wasted and inefficient.

  An object of this invention is to provide the refrigerator which can reduce power consumption by carrying out the light emission control of the illumination means which activates a photocatalyst efficiently.

  A feature of the present invention is that a gas sensor for detecting a gas concentration of a target gas to be processed using a photocatalyst such as an organic gas or an odor component is provided in the storage chamber, and the state in the storage chamber is determined based on a detection value of the gas sensor. When the concentration is lower than a predetermined value, the light emission control is performed such as suppressing or stopping the light emission of the illumination means for activating the photocatalyst.

  According to the present invention, the necessity of activation of the photocatalyst is determined based on the detected gas concentration of the target gas, and thereby the illumination means that activates the photocatalyst is efficiently controlled, thereby suppressing use of unnecessary power. Thus, energy saving can be improved.

It is a center longitudinal cross-sectional view of the refrigerator with which this invention is applied. It is a cross-sectional perspective view of the lowest space part of the refrigerator compartment which is one of the storage rooms which becomes one Example of this invention. It is a longitudinal cross-sectional view of the sealed storage chamber formed in the refrigerator compartment shown in FIG. It is a front view of the back panel of the refrigerator compartment shown in FIG. It is a control block diagram of the refrigerator which becomes one Example of this invention. It is a characteristic diagram for explaining the specific one CO ₂ sensor for measuring carbon dioxide (CO ₂₎ is a component of the CO ₂ concentration and the output voltage of the target gas. It is a timing chart figure explaining the operation timing of the illumination means of the photocatalyst which becomes one example of the present invention. It is a timing chart figure explaining the operation timing of the illumination means of the photocatalyst which becomes other examples of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments, and various modifications and application examples are included in the technical concept of the present invention. Is also included in the range.

  The first embodiment of the present invention will be described below. First, the configuration of the refrigerator will be described with reference to FIGS. 1 and 2. FIG. 1 is a central longitudinal sectional view of the refrigerator, and FIG. 2 is a sectional perspective view of the lowermost space portion of the refrigerator compartment shown in FIG.

  As is clear from these drawings, the refrigerator includes a refrigerator body 1 and a plurality of doors 6, doors 7, doors 9, and doors 10 provided on the front surface thereof. The refrigerator body 1 is composed of a steel plate outer box 11, a resin inner box 12, a urethane foam heat insulating material 13 and / or a vacuum heat insulating material (not shown) filled therebetween, From the top of the figure, a plurality of storage rooms are formed in the order of the refrigerator compartment 2, the freezer compartment 3, the freezer compartment 4, and the vegetable compartment 5.

  In other words, the refrigerator compartment 2 is arranged at the top and the vegetable compartment 5 is divided and arranged at the bottom, and both the compartments are provided between the refrigerator compartment 2 and the vegetable compartment 5. A freezer compartment 3 and a freezer compartment 4 that are thermally partitioned from each other are disposed. The refrigerator compartment 2 and the vegetable compartment 5 are storage compartments in a refrigerated temperature zone, and the freezer compartment 3 and the freezer compartment 4 have a freezing temperature zone of 0 ° C. or less (for example, a temperature zone of about −20 ° C. to −18 ° C.). It is a storage room. These storage chambers 2 to 5 are partitioned by partition walls 34, 35, and 36.

  As described above, the front surface of the refrigerator main body 1 has a door 6, a door 7, a door 9 and a door 9, respectively, in order to close the front opening of the refrigerator compartment 2, the freezer compartment 3, the freezer compartment 4, and the vegetable compartment 5. And a door 10 is provided. The freezer compartment door 6 closes the front opening of the freezer compartment 2, the freezer compartment door 7 closes the front opening of the freezer compartment 3, and the freezer compartment door 9 closes the front opening of the freezer compartment 4. The vegetable compartment door 10 is a door that closes the front opening of the vegetable compartment 5. The refrigerator compartment door 6 is a double door with double doors, and the freezer compartment door 7, the freezer compartment door 9, and the vegetable compartment door 10 are constructed with drawer doors. The structure is drawn out.

  The refrigerator body 1 having the above-described structure is provided with a refrigeration cycle. This refrigeration cycle includes a compressor 14, a condenser (not shown), a capillary tube (not shown) and an evaporator 15, and again a compressor 14 connected in that order. The compressor 14 and the condenser are installed in a machine room provided at the lower back of the refrigerator body 1. The evaporator 15 is installed in a cooler room provided behind the freezing rooms 3 and 4, and a blower fan 16 is installed above the evaporator 15 in the cooler room.

  The cold air cooled by the evaporator 15 is sent to each storage room such as the refrigerator compartment 2, the freezer compartments 3, 4 and the vegetable compartment 5 by the blower fan 16 through a cold air passage (not shown). Specifically, a part of the cold air sent by the blower fan 16 is sent to a storage room in the refrigeration temperature zone of the refrigeration room 2 and the vegetable room 5 via a damper that can be opened and closed. The part is sent to the freezer compartment 3 and the storage compartment of the freezing temperature zone.

  The cool air sent to the storage rooms of the refrigerator compartment 2, the freezer compartments 3 and 4 and the vegetable compartment 5 by the blower fan 16 is returned to the cooler compartment through the cool air return passage after cooling each storage compartment. . Thus, the refrigerator which becomes this Embodiment has the circulation structure of cold air, and maintains each store room 2-5 at a suitable temperature.

  Further, a plurality of shelves 17 to 20 made of transparent resin plates are detachably installed in the refrigerator compartment 2. The lowermost shelf 20 is installed so as to be in contact with the back surface and both side surfaces of the inner box 12 and divides a so-called lowermost space 21, which is a lower space, from the upper space. A plurality of door pockets 25 to 27 are installed inside each refrigerator compartment door 6, and these door pockets 25 to 27 protrude into the refrigerator compartment 2 with the refrigerator compartment door 6 being closed. It is provided as follows. A back panel 30 that forms a passage through which the cool air supplied from the blower fan 16 passes is provided on the back of the refrigerator compartment 2.

  As clearly shown in FIG. 2, the lowermost space portion 21 is sealed (and further depressurized) in order from the left, the ice making water tank 22 for supplying ice making water to the ice making tray of the freezing room 3, and the room. Sealed storage chambers 24 are provided for maintaining the freshness of food and storing it for a long time. The sealed storage chamber 24 has a width that is narrower than the width of the refrigerating chamber 2 and is disposed adjacent to the side surface of the refrigerating chamber 2.

  The sealed storage chamber 24 is provided with a photocatalyst targeted by the present invention and a light emitting diode as an illuminating means thereof, and is configured to deodorize odorous components and organic gases generated from food in the sealed storage chamber 24 by the photocatalyst. Has been.

  As is clear from FIG. 3, the sealed storage chamber 24 is surrounded by walls and doors so as to be airtight. Therefore, movement of the internal gas and the external gas can be suppressed. . Furthermore, the internal pressure can be made lower than the atmospheric pressure by connecting the pressure reducing means.

  An opening is provided on the top surface of the sealed container, and the opening is covered with a transparent flat plate 52 coated with a photocatalyst paint activated by visible light such as tungsten oxide, and sealed with a gasket 53. A lid member 51 on which a substrate on which a light-emitting diode 46 that emits visible light (white) is mounted is provided on the outside, and the lid member 51 plays a role of sealing the opening by pressing the flat plate 52.

  Next, details of the back panel 30 shown in FIG. 1 will be described with reference to FIG. The rear panel 30 includes a cold air discharge port (first cold air discharge port) 31 for supplying cold air to the refrigerating chamber 2 and a sealed storage chamber for supplying cold air to the lowermost space 21 of the refrigerating chamber 2. A cooling air discharge port (second cold air discharge port) 32 for cooling and a cold air return port 33 are provided. The cold air return port 33 is provided on the rear side of the closed storage chamber 24 on the side close to the side surface of the refrigerator compartment 2.

  Further, the cold air discharge port 32 is provided toward the gap between the upper surface of the sealed storage chamber 24 and the lower surface of the shelf 20. The cold air discharged from the cold air discharge port 32 flows through the gap between the upper surface of the sealed storage chamber 24 and the lower surface of the shelf 20, and cools the sealed storage chamber 24 from the upper surface. Therefore, the inside of the sealed storage chamber 24 is indirectly cooled.

  In addition, a damper device 41 for controlling the flow of cold air into the sealed storage chamber 24 is provided on the upstream side of the cold air discharge port 32. The opening and closing of the damper device 41 is controlled by a control device (not shown), and thereby the amount of cold air supplied to the sealed storage chamber 24 is controlled.

  Further, as shown in FIG. 1, for example, a heater 43 is provided in order to increase the temperature in the sealed storage chamber 24. The heater 43 is provided on a lower projection surface in the sealed storage chamber 24. In this example, the heater 43 has a surface area approximately the same as the bottom surface in the sealed storage chamber 24.

  Here, the closed storage chamber 24 is disposed close to the right side surface of the refrigerator compartment 2 to eliminate the gap on the right side of the closed storage chamber 24, and a shelf (not shown) is provided at the left end of the upper surface of the closed storage chamber 24. Since the partition wall is provided to eliminate the gap on the upper left side of the sealed storage chamber 24, the cold air discharged from the cold air discharge port 32 is not stored in the sealed storage chamber 24 without being divided into the left and right sides. It flows on the upper surface of the chamber 24.

  Thereby, the inside of the sealed storage chamber 24 can be cooled quickly by increasing the amount of cool air that cools the upper surface of the sealed storage chamber 24. The cold air that has cooled the upper surface of the closed storage chamber 24 is sucked into the cold air return port 33 from the front of the closed storage chamber 24 through the left side surface of the closed storage chamber 24, and returned to the cooler chamber through the cold air return passage. It is. Since the cold air return port 33 is provided on the rear side of the closed storage chamber 24 and on the side close to the side surface of the refrigerator compartment 2, the cold air contacts the back surface and the left side surface of the closed storage chamber 24 and cools it.

  Thus, the sealed storage chamber 24 is indirectly cooled by passing cold air outside. Therefore, by reducing the convection of the cold air by reducing the pressure, and by indirectly cooling in the sealed container, the effects of the compressor on / off and the temperature rise such as opening / closing the refrigerator door and defrosting However, the adverse effect on the internal temperature can be suppressed, and the constant temperature and high humidity can be maintained. The cold air that has cooled the entire refrigerator compartment 2 is also sucked into the cold air return port 33.

An ice making water pump 28 is installed behind the ice making water tank 22. A negative pressure pump 29, which is an example of a decompression device for decompressing the sealed storage chamber 24, is disposed in the space behind the drawer case 23 and behind the sealed storage chamber 24. The negative pressure pump 29 is accommodated in a storage case (not shown). In addition to the negative pressure pump 29, the CO ₂ sensor 45 whose electrical output changes depending on the concentration of ambient CO ₂ is contained in the storage case. (Not shown) is accommodated.

As this CO ₂ sensor, any of a semiconductor type, a solid electrolyte type, and an infrared type may be used. In this embodiment, a semiconductor type is used.

In the present embodiment, the air in the sealed storage chamber 24 and sucked by the negative pressure pump 29 is arranged to diffuse around the CO ₂ sensor 45 in the housing case, the electrical output of the CO ₂ sensor 45 The detection operation is performed when the negative pressure pump 29 is turned on. The negative pressure pump 29 is connected to a pump connection portion provided on the side surface of the sealed storage chamber 24 via a conduit.

  Further, as shown in FIG. 2, the above-described sealed storage chamber 24 includes a box-shaped sealed storage chamber main body 40 having an opening for taking in and out food (opening portion for taking in and out food), and a closed storage chamber main body 40. A closed storage chamber door 50 that opens and closes the opening / closing opening for food and a food tray 60 that stores food in the closed storage chamber 24 through the closed storage chamber door 50 and into / out of the closed storage chamber 24 are provided. That is, in the closed storage chamber main body 40, as a low-pressure space in which the space surrounded by the closed storage chamber main body 40 and the closed storage chamber door 50 is depressurized by closing the food storage opening / closing opening of the closed storage chamber door 50. It is formed. The food tray 60 is attached to the back side of the sealed storage room door 50 and can be moved back and forth with the movement of the closed storage room door 50.

  The closed storage chamber 24 is loaded with food on the food tray 60 and the closed storage chamber door 50 is closed, so that the inside of the closed storage chamber 24 is closed, and the door open / close switch that detects the opening / closing of the refrigerator compartment door is turned on and negative. The pressure pump 29 is driven to depressurize the sealed storage chamber 24 to a state lower than the atmospheric pressure. Thereby, the oxygen concentration in the sealed store room 24 can be reduced, and deterioration of nutritional components in the food can be prevented.

Furthermore, after the sealed storage chamber 24 is sealed and depressurized, the light-emitting diode 46 provided on the ceiling is turned on to activate the photocatalyst applied to the flat plate 52. As a result, the odor component and organic gas in the food are changed to CO ₂ and the inside of the sealed container can be deodorized. In addition, the activity of enzymes and cells of foods such as meat and vegetables can be suppressed by setting the inside of the sealed container to an inert atmosphere with a high CO ₂ concentration.

  Then, by pulling the closed storage chamber door 50 forward, the pressure release valve provided in a part of the closed storage chamber door 50 operates to release the reduced pressure state of the closed storage chamber 24. As a result, the atmospheric pressure The closed storage chamber door 50 can be opened. Thus, the sealed storage chamber door 50 can be easily opened and food can be taken in and out.

  Next, the temperature switching control method in the refrigerator of the present embodiment will be described with reference to FIG. In addition, FIG. 5 is a control block diagram for demonstrating the control method of the refrigerator of a present Example.

  In FIG. 5, for example, a control device 46 configured by a microcomputer or the like includes a temperature detected by a temperature sensor 42 that detects a temperature of the refrigerator compartment 2, a refrigerator compartment 2 that is a storage compartment, a freezer compartment 3, and a freezer compartment. 4. The temperature set by the temperature adjusting unit 44 in which the temperature of the vegetable compartment 5 is set is input, and control signals to the damper device 41 and the heater 43 are output based on those temperatures. Further, the temperature of the sealed storage chamber 24 can be switched between an ice temperature temperature zone or a chilled temperature zone.

  Since the control device 46 is composed of a microcomputer as described above, various controls such as temperature control (damper control, heater control, compressor control, etc.) and light emission control of the light emitting diode are built-in nonvolatile. It is executed by a program stored in a memory, for example, a flash memory.

  Specifically, when the temperature detected by the temperature sensor 42 is lower than a certain reference temperature A, the amount of cold air is controlled (suppressed) by reducing the opening degree of the damper device 41 or completely closing it. In addition, when the temperature becomes too low, the heater 43 is energized to increase the temperature.

  On the other hand, when the temperature detected by the temperature sensor 42 is higher than the reference temperature A, the opening degree of the damper device 41 is increased, and cold air is supplied to the cold air circulation space in the closed storage chamber 24 to Control is performed to lower the temperature.

Further, in the present embodiment, the temperature adjustment unit 44 can be set to “auto mode” for automatically switching between the ice temperature temperature range and the chilled temperature range, and the food storage temperature range can be switched by the CO ₂ sensor 45. It is set as the structure determined based on the electrical output.

For example, when vegetables are stored in the sealed storage chamber 24 in a state where the light-emitting diode 46 is not illuminated and the catalytic function of the photocatalyst is not exerted, the vegetables are sealed and stored by the breathing action of the vegetables within a predetermined time. The CO ₂ concentration in the chamber 24 increases. Air sealed storage chamber 24 by the negative pressure pump 29 is turned on in this state is introduced into the storage case, is spread around the CO ₂ sensor 45, the electrical output of the CO ₂ sensor 45 is reduced. On the other hand, when meat and fish are stored, the CO ₂ concentration within a predetermined time hardly changes because there is no respiratory action like vegetables, so the electrical output does not change as much as the left. At this time, since the catalytic function does not work, organic gas and odor components from meat and fish are not converted to CO ₂ .

By utilizing this characteristic, it is possible to distinguish food attributes such as meat and fish from vegetables. That is, when the electrical output of the CO ₂ sensor 45 is reduced without illumination by the light emitting diode 46, it is determined that the vegetables are stored, and the chilled temperature range is switched, and the electrical output does not change as much as the left. In such a case, it is determined that meat and fish are preserved, and control is performed to automatically switch to the ice temperature range. As a result, an “auto mode” setting that automatically switches between the ice temperature temperature range and the chilled temperature range is possible.

Next, after the determination of the food is completed, energization to the light emitting diode 46 is started, and the photocatalyst applied to the flat plate 52 is activated. As described above, when food is contained, CO ₂ is generated by the deodorizing action of the photocatalyst, so that the CO ₂ concentration in the closed storage chamber 24 increases. Energization of the light emitting diode 46 is continued as long as the sealed inside of the sealed storage chamber 24 is maintained.

When the inside of the sealed storage chamber 24 is continuously sealed for a long time, the negative pressure pump is periodically turned on to reduce the pressure in the sealed container in order to correct the pressure increase due to the minute leakage of the sealed container. . At this time, if the food is contained, the organic gas and odor components based on the food are converted to CO ₂ by the action of the photocatalyst, so the CO ₂ concentration in the sealed container is increased and the air in the sealed container is stored. When led into the case, the electrical output of the CO ₂ sensor will decrease. In this case, since organic gas and odor components from meat and fish are converted to CO ₂ by the photocatalyst, the concentration tends to increase with time.

However, when no food is stored in the closed storage chamber 24, organic gas and odor components do not exist in the first place. Therefore, even if the photocatalyst is activated by the light emitting diode 46, the CO ₂ concentration does not change, and the CO ₂ sensor. The electrical output of is kept unchanged.

By utilizing this characteristic, it is possible to distinguish whether food (for example, meat, fish, vegetables, etc.) is contained in the closed storage chamber 24 or not. That is, when the electrical output of the CO ₂ sensor 45 is reduced, it is determined that food is stored in the storage chamber 24, and the deodorizing action by the photocatalyst is continuously performed by continuing energization of the light emitting diode 46. Control to enable.

On the other hand, when the electrical output of the CO ₂ sensor 45 does not change, it is determined that no food is stored, and the power supply to the light emitting diode 46 is stopped, thereby invalidating the catalytic function of the photocatalyst and suppressing power consumption. To control.

Here, in the present embodiment, the light emission control of the light emitting diode 46 is performed by the CO ₂ sensor 45. In short, it is sufficient if it is possible to determine whether to activate or deactivate the catalytic function of the photocatalyst. The CO ₂ sensor 45 may not be used.
Next, a method for detecting a change in the CO ₂ concentration in the sealed storage chamber 24 by the CO ₂ sensor 45 and controlling the light emitting diode 46 will be described with reference to FIGS. 6 and 7. The control of the negative pressure pump 29 and the light emitting diode 46 according to the operation timing chart shown in FIG. 7 is executed by a program stored in the flash memory of the microcomputer.

As in Figure 6, CO ₂ sensor 45 is a module using a semiconductor-type CO ₂ sensor producing electrical output of 0~5V by the concentration of the surrounding CO ₂ (ppm), for example, sealed storage chamber 24 When the CO ₂ concentration is Cx (ppm), the voltage Vx (V) is output from the CO ₂ sensor 45. Based on the value of the voltage Vx, the control device 46 detects the CO ₂ concentration in the sealed storage chamber 24 to perform temperature control and control of the light emitting diode 46.

However, CO ₂ contained in the originally atmosphere in a sealed storage chamber _24, CO ₂ generated from the food, such as CO ₂ contained in human breath entering when storing food are mixed. For this reason, simply measuring the voltage Vx cannot separate and detect CO ₂ generated from food and CO ₂ increased by the catalytic action of the photocatalyst.

A method for isolating the CO ₂ generation factor will be described with reference to an operation timing chart shown in FIG.

  First, as shown in FIG. 7A, when the refrigerator compartment door 6 changes from “closed” → “open” → “closed”, it is determined that there is a possibility that the food has been stored. As shown in (b), the negative pressure pump 29 is driven for the Ta time at the same time as “closed” or after a predetermined time has elapsed. At this time, since the driving of the light emitting diode 46 is stopped as shown in FIG. 7C, the photocatalyst is in a state of stopping its catalytic function.

In this state, as shown in FIG. 7 (d), the air in the hermetic container sucked by the negative pressure pump 29 is a mixture of the atmosphere and CO ₂ due to human breath, and the concentration is Ca (ppm). It has become.

Therefore, as shown in FIG. 7E, the voltage detected by the CO ₂ sensor 45 is not so high in CO ₂ concentration, so the voltage during the period in which the negative pressure pump 29 is driven becomes the minimum value Va. ing. (As the negative pressure pump 29 operates, the CO ₂ concentration flowing to the CO ₂ sensor 45 increases, so the voltage detected by the CO ₂ sensor 45 decreases.) The CO in the sealed storage chamber 24 detected at this time is detected. As described above, the ₂ concentration Ca is a mixture of CO ₂ contained in the atmosphere and CO ₂ contained in the exhalation of a person who flows in during storage. As a result, the atmosphere in the storage chamber 24 is set to an initial state, and the CO ₂ concentration at this time is a criterion for the following determination.

Thereafter, as shown in FIG. 7B, the negative pressure pump 29 is again driven for Tb time after a waiting time of T1 time (for example, several tens of minutes), and within the period during which the negative pressure pump 29 is driven. The minimum value of the voltage at is Vb. (As the negative pressure pump 29 operates, the CO ₂ concentration flowing to the CO ₂ sensor 45 increases, so the voltage detected by the CO ₂ sensor 45 decreases.) At this time, the driving of the light emitting diode 46 is stopped. Therefore, the photocatalyst is in a state of stopping its catalytic function.

Here, when vegetables are stored in the sealed storage chamber 24, the CO ₂ concentration inside the sealed container rises during the T1 time due to the breathing action of the vegetables. On the other hand, when foods that do not emit CO ₂ such as meat and fish are stored, the CO ₂ concentration hardly changes. This is because the catalytic function of the photocatalyst is stopped even if odor components or organic gases are generated. At this time, the CO ₂ concentration in the sealed storage chamber 24 is as high as Cb (ppm) as shown in FIG.

  Therefore, in the control device 46, it is possible to determine (estimate) that meat and fish are stored when Vb = Va and vegetables are stored when Va> Vb.

Further, the CO ₂ concentration emitted from the food is expressed by Va−Vb, and the increase rate of the CO ₂ concentration is higher as the value of Va−Vb is larger. That is, it can be determined that more vegetables are stored.

Here, the relationship between the Ta time, which is the driving time of the negative pressure pump 29, and the Tb time has a relationship of Ta time <Tb time. The reason for this is that when the first negative pressure pump 29 is driven (Ta time), the air pressure in the sealed storage chamber 24 is high because the refrigerator door 6 is operated from “closed” → “open” → “closed”. When the next negative pressure pump 29 is driven (Tb time), the air in the sealed storage chamber 24 has already been decompressed. That is, since the difference in the amount of air flowing to the CO ₂ sensor 45 appears due to the level of the atmospheric pressure, the Tb time is lengthened to increase the detection accuracy.

Next, as shown in (b) of FIG. 7, the negative pressure pump 29 is operated only for Tb time, and thereafter, the negative pressure pump 29 is stopped as shown in (c) of FIG. After the elapse of time, energization of the light emitting diode 46 is started to supply light energy to the photocatalyst to activate the catalytic function. In this state, organic gas and odor components generated from vegetables, meat, fish and the like are converted to CO ₂ by the catalytic function of the photocatalyst. At this time, the CO ₂ concentration in the sealed storage chamber 24 is as high as Cc (ppm) as shown in FIG.

Thereafter, the negative pressure pump 29 is driven again for Tc time after T2 time (several hours) as shown in FIG. 7B, and this negative pressure pump 29 is returned as shown in FIG. The minimum value of the voltage within the period during which is driven is Vc. (Since the CO ₂ concentration flowing to CO ₂ sensor 45 as a negative pressure pump 29 is operated is high voltage detected by the CO ₂ sensor 45 becomes lower.)
Here, when food is stored in the closed storage chamber 24, the CO ₂ concentration in the closed storage chamber 24 is increased by the catalytic function of the photocatalyst by irradiation of light from the light emitting diode 46, and conversely, the food When not stored, the CO ₂ concentration hardly changes. That is, in the control device 46, it is possible to determine that no food is stored when Vc = Vb, and that food such as vegetables, meat, and fish is stored when Vb> Vc. In the state of FIG. 7, energization is continued to the light emitting diode 46 on the assumption that food is stored.

  Therefore, when it is determined that food is stored, the light-emitting diode 46 is kept energized to supply light energy to the photocatalyst. When it is determined that food is not stored, the light-emitting diode 46 is turned off. Thus, the supply of light energy to the photocatalyst is stopped.

Thus, the negative pressure pump 29 a photocatalyst in a state that does not activate driven twice at an interval of time T1, determine that CO ₂ from any food from changes in the concentration of CO ₂ at this time is generated (Estimation) can be performed.

In addition, with the photocatalyst activated, the negative pressure pump 29 is driven again after a time interval of T2, and it is detected whether there is CO ₂ increased by the catalytic function of the photocatalyst from the change in CO ₂ concentration at this time. In addition, the presence or absence of food in the storage room 24 can be determined. Then, when it is determined that there is no food in the storage chamber 24, the light-emitting diode 46 is turned off, so that the catalytic function of the photocatalyst can be disabled and the power consumption can be suppressed.

  In this embodiment, when it is determined that there is no food in the storage chamber 24, the power supply to the light emitting diode 46 is stopped. However, instead of stopping the power supply, the amount of power supply is reduced to generate light energy. It is also possible to suppress power consumption by reducing the amount.

  In this embodiment, the T2 time is left and the negative pressure pump 29 is driven between the Tb time and the Tc time to determine the presence or absence of food in the sealed storage chamber 24. However, the present invention is not limited to this. By adding this operation, the presence or absence of food in the sealed storage chamber 24 may be determined.

  Next, the second embodiment of the present invention will be described with reference to FIG. 8, but since it overlaps in many parts with FIG. 7, the description of the overlapping parts will be omitted.

The semiconductor CO ₂ sensor 45 used in the refrigerator described in the first embodiment has a characteristic that the sensor sensitivity changes depending on the temperature and humidity around the sensor and the electrical output also changes.

Therefore, if the temperature or humidity is changed as shown in FIG. 7, despite the CO ₂ concentration is increased, it becomes first-time measurement value Va and second time values measured value Vb is near the, the CO ₂ concentration is increased May be falsely detected.

Therefore, a method for accurately measuring the CO ₂ concentration in the sealed storage chamber 24 even when the ambient temperature or humidity changes will be described. Here, in FIG. 8, the opening / closing of the freezer compartment door, the operation of the negative pressure pump 29, the energization state of the light emitting diode 46, and the like are the same as in FIG.

First, as shown in FIG. 8A, the maximum value Vamax and the minimum value Vamin of the electrical output of the CO ₂ sensor 45 are measured within a period of Ta time that is the driving time of the negative pressure pump 29. Further, the amount of change ΔVa = (Vamax−Vamin) is obtained from this measured value.

The change amount ΔVa of the electrical output of the CO ₂ sensor 45 at this time can be regarded as a detected value of the CO ₂ concentration at the temperature and humidity within the Ta time.

Similarly, the maximum values Vbmax and Vcmax and the minimum values Vbmin and Vcmin of the electrical output of the CO ₂ sensor 45 within the period of Tb time and Tc time are measured. Further, the amount of change ΔVb = (Vbmax−Vbmin) is obtained from this measured value. Further, the amount of change ΔVc = (Vcmax−Vcmin) is obtained from this measured value.

At this time, the change amount ΔVb and the change amount ΔVc of the electrical output can be regarded as the detected values of the CO ₂ concentration at the temperature and humidity within the period of Tb time and Tc time, respectively.

Here, since ΔVa, ΔVb, and ΔVc are measured values in the respective measurement environments, changes in the electrical output due to the influence of temperature and humidity are excluded, and changes in the electrical output due to increase / decrease in the CO ₂ concentration are captured. It can be said.

Therefore, if ΔVa = ΔVb, it is determined that no meat, fish, or anything is stored in the sealed storage chamber 24. If ΔVb> ΔVa, the CO ₂ concentration in the sealed storage chamber 24 increases during the T1 time. It can be determined that the vegetables are stored. In addition, when ΔVb = ΔVc, no food is stored in the sealed storage chamber, and when ΔVc> ΔVb, it can be determined that the food is stored in the sealed storage chamber during T2.

  It should be noted that ΔVb = ΔVc does not necessarily have to be equal, but includes determining that they are substantially equal within a predetermined width.

The detection accuracy of the CO ₂ sensor 45 can be further improved by the measurement method as described above.

  In the present embodiment, which is the first embodiment and the second embodiment, the refrigerator in which the photocatalyst and the light emitting diode are provided in the sealed storage chamber has been described. However, the present invention is not limited to this and has been described in the related art. Such a refrigerator can also be applied. In short, the present invention can be applied to a refrigerator provided with a device for illuminating and activating a photocatalyst with illumination means.

  As described above, according to the present invention, a gas sensor for detecting the gas concentration of the target gas to be processed using a photocatalyst such as an organic gas or an odor component is provided in the storage chamber, and the state in the storage chamber is determined by the detection value of the gas sensor. If the target gas concentration is lower than a predetermined value, light emission control is performed such as suppressing or stopping the light emission of the illumination means for activating the photocatalyst.

  According to the present invention as described above, the necessity of activation of the photocatalyst is determined based on the detected gas concentration of the target gas, and thereby the illumination means for activating the photocatalyst is efficiently controlled, so that wasteful power is consumed. Use can be suppressed and energy saving performance can be improved.

DESCRIPTION OF SYMBOLS 1 ... Refrigerator body, 2 ... Refrigeration room, 3, 4 ... Freezing room, 5 ... Vegetable room, 6 ... Refrigeration room door, 7, 9 ... Freezing room door, 10 ... Vegetable room door, 11 ... Outer box, 12 ... Inside Box, 13 ... Foam insulation, 14 ... Compressor, 15 ... Evaporator, 16 ... Blower fan, 24 ... Sealed storage room, 25-27 ... Door pocket, 28 ... Ice water pump, 30 ... Back panel, 31 ... No. DESCRIPTION OF SYMBOLS 1 cold air discharge port, 32 ... 2nd cold air discharge port, 33 ... Cold air return port, 34-36 ... Partition wall, 37 ... Cold air return channel | path, 40 ... Sealed storage chamber main body, 41 ... Damper apparatus, 42 ... Temperature sensor , 43 ... heater, 44 ... temperature control unit, 45 ... CO ₂ sensor, 46 ... light-emitting diode, 47 ... controller, 50 ... sealed storage compartment door, 51 ... lid portion, 52 ... flat plate, 53 ... gasket, 60 ... Food tray.

Claims (2)

A plurality of storage rooms provided in the refrigerator body ;
A cold air passage for sending cold air to the plurality of storage rooms ;
A storage room door for opening and closing the storage room ;
A sealed storage chamber provided in one of the plurality of storage chambers ;
A vacuum pump for discharging the gas in the sealed storage chamber to the outside ;
A photocatalyst provided in the sealed storage chamber ;
Illuminating means provided in the sealed storage chamber for supplying light energy to the photocatalyst to activate the photocatalyst ;
A gas sensor for detecting a gas concentration of at least one gas component present in the sealed storage chamber ;
Illumination control means for controlling light energy of the illumination means according to a detection value of the gas sensor ,
The illumination control means sets a predetermined time from the first predetermined time to a first difference between a maximum value and a minimum value of the detection value of the gas sensor within a first predetermined time when the vacuum pump is driven. Comparing the second difference between the maximum value and the minimum value of the detected value of the gas sensor within a second predetermined time when the vacuum pump is driven after a lapse of time, the second difference is the first difference When the difference is larger than the difference, the light energy is supplied by the lighting means assuming that there is food in the sealed storage room, and when the second difference is substantially equal to the first difference, A refrigerator characterized by stopping or suppressing the supply of light energy by the lighting means on the assumption that there is no food . The refrigerator according to claim 1 ,
The refrigerator is characterized in that the gas sensor is a CO2 sensor whose sensor detection value increases or decreases depending on the CO2 concentration, and is a semiconductor type, a solid electrolyte type, or an infrared type .

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